4-letter word everyone in Delhi needs to know: dust (Beyond smoke and car exhaust, a critical pollutant in the city is toxic dust hiding in plain sight. Common solutions offer limited benefits), Pg13

Key Highlights:

• A January 2026 report by the CAQM identified road dust as a major pollution source in Delhi, acting as both a primary emission and a persistent source.
• Road dust includes airborne dust from roads, vehicle movement, dry soil, road wear, and debris from construction and demolition material.
• A CAQM committee reported that resuspension is driven by continuous dust deposits, unsuitable road infrastructure, poor maintenance, and inadequate dust-management practices.
• A 2023 multi-city study indicated that as exhaust emissions decline, non-exhaust sources like road dust, tyre wear, and brake wear are gaining significance.
• Exposure to road dust is linked to over 10,207 premature deaths annually nationwide.

Detailed Insights:

• Road dust is a line source, requiring corridor-wide, routine removal and surface management, unlike construction dust which is a point source needing site-level containment.
• Unpaved medians, improper irrigation practices, encroachments, and unauthorized parking contribute to dust accumulation by obstructing cleaning efforts.
• Local roads and secondary streets are often excluded from regular maintenance schedules, leading to prolonged dust emissions after significant road damage.
• Mechanical Road Sweeping Machines (MRSMSs) and sanitation workers are deployed, but mechanised sweeping needs to become more scientific with standard operating procedures.
• Delhi's natural environment, including dry summers, dust storms, loose alluvial soil, and low rainfall, contributes to a baseline level of dust that requires active management.
• Anti-smog guns and water sprinklers offer limited benefits as they merely transport dust and can lead to re-suspension once the surface dries.
• A standardized framework combining paving, greening, and improved maintenance practices is needed, along with roadside planting of drought-resilient species.
• Road dust is a major source of PM2.5 and PM10, which can cause lung irritation, worsen respiratory conditions, and lead to premature death and reduced lung function growth in children.

Key Concepts Involved:

• PM2.5 and PM10: Fine particulate matter that can penetrate deep into the lungs and bloodstream, causing respiratory and cardiovascular issues.
• Resuspension: The process by which deposited dust particles are re-introduced into the air due to vehicular movement or wind.
• Silt Load: The quantity of fine particulate matter present on road surfaces, contributing to dust pollution when resuspended.